Though Spelling, 38, previously joked that it was her husband's insatiable sex drive that led to her unplanned pregnancy, McDermott says he doesn't regret ignoring the doctor's orders to wait at least six weeks before getting intimate.

"It's so funny how everyone blames the man," the actor says. "It's like, 'Oh my God, will you leave your wife alone?' But it takes two to tango. She wasn't putting up that much of a fight. But I have big shoulders. I'll take it."

During her CelebraTori book launch in New York earlier this month, Spelling joked that daughter Hattie, 6 months, "had a lot to say" about getting a younger sibling. "She was up in arms. She tossed that paci right out the door. Furious."

Liam, 5, and Stella, 3, were "over-the-moon and super excited" to learn they'd be getting another sibling this fall. (McDermott is also father to son Jack, 13, from a previous marriage.)

McDermott assures Celebuzz that their latest journey will be chronicled in future episodes of their Oxygen reality show. "Tori and I love the fact that we get to work together," he explains. "We get to work with Liam and Stella; we get to stay together as a family. As long as people want to see us, we'll keep making the show."